Sternenlabor/WLED
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Switch trigonometric implementation, saves 460b memory

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cschwinne
2021-04-14 16:49:47 +02:00
parent 5751d5c1b0
commit f3b84f1365
4 changed files with 85 additions and 9 deletions
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17
wled00/ntp.cpp
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@@ -1,5 +1,6 @@
#include "src/dependencies/timezone/Timezone.h"
#include "wled.h"
#include "wled_math.h"
/*
* Acquires time from NTP server
@@ -316,8 +317,8 @@ void checkTimers()
// get sunrise (or sunset) time (in minutes) for a given day at a given geo location
int getSunriseUTC(int year, int month, int day, float lat, float lon, bool sunset=false) {
//1. first calculate the day of the year
float N1 = floor(275 * month / 9);
float N2 = floor((month + 9) / 12);
float N1 = 275 * month / 9;
float N2 = (month + 9) / 12;
float N3 = (1 + floor((year - 4 * floor(year / 4) + 2) / 3));
float N = N1 - (N2 * N3) + day - 30;
@@ -329,10 +330,10 @@ int getSunriseUTC(int year, int month, int day, float lat, float lon, bool sunse
float M = (0.9856 * t) - 3.289;
//4. calculate the Sun's true longitude
float L = fmod(M + (1.916 * sin(DEG_TO_RAD*M)) + (0.020 * sin(2*DEG_TO_RAD*M)) + 282.634, 360.0);
float L = fmod(M + (1.916 * sin_t(DEG_TO_RAD*M)) + (0.020 * sin_t(2*DEG_TO_RAD*M)) + 282.634, 360.0);
//5a. calculate the Sun's right ascension
float RA = fmod(RAD_TO_DEG*atan(0.91764 * tan(DEG_TO_RAD*L)), 360.0);
float RA = fmod(RAD_TO_DEG*atan_t(0.91764 * tan_t(DEG_TO_RAD*L)), 360.0);
//5b. right ascension value needs to be in the same quadrant as L
float Lquadrant = floor( L/90) * 90;
@@ -343,16 +344,16 @@ int getSunriseUTC(int year, int month, int day, float lat, float lon, bool sunse
RA /= 15.;
//6. calculate the Sun's declination
float sinDec = 0.39782 * sin(DEG_TO_RAD*L);
float cosDec = cos(asin(sinDec));
float sinDec = 0.39782 * sin_t(DEG_TO_RAD*L);
float cosDec = cos_t(asin_t(sinDec));
//7a. calculate the Sun's local hour angle
float cosH = (sin(DEG_TO_RAD*ZENITH) - (sinDec * sin(DEG_TO_RAD*lat))) / (cosDec * cos(DEG_TO_RAD*lat));
float cosH = (sin_t(DEG_TO_RAD*ZENITH) - (sinDec * sin_t(DEG_TO_RAD*lat))) / (cosDec * cos_t(DEG_TO_RAD*lat));
if (cosH > 1 && !sunset) return 0; // the sun never rises on this location (on the specified date)
if (cosH < -1 && sunset) return 0; // the sun never sets on this location (on the specified date)
//7b. finish calculating H and convert into hours
float H = sunset ? RAD_TO_DEG*acos(cosH) : 360 - RAD_TO_DEG*acos(cosH);
float H = sunset ? RAD_TO_DEG*acos_t(cosH) : 360 - RAD_TO_DEG*acos_t(cosH);
H /= 15.;
//8. calculate local mean time of rising/setting